• Welcome to ClassicBroncos! - You are currently viewing the forums as a GUEST. To take advantage of all the site features, please take a moment to register. It's fast, simple and absolutely free. So please join our community today!
    If you have problems registering or can't log into your account, please contact Admin.

Rear axle flex /travel mods ?

patford

New Member
Joined
Dec 12, 2010
Messages
28
Need to increase the rear axle flex to keep up with the front after longer coil install . Have wh 2.5 " lift leaf and looking for the next step to try other than just go 3.5 or 4.5 . toyota guys seem to make the f150 2wd 80 /96 leaf work .Have no problem of moving mounts what have people done to increase travel/flex of there leafs . Some good reading but need more . http://classicbroncos.com/forums/showthread.php?t=271707&highlight=rear+travel
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
47,355
Leaf rockers is one way.
Longer shocks, possibly with different shock mounting orientation.

What style of rear leaf is in there now?
Are you sure the leaf packs are the limiting factor at this point? Or could it be shocks, or other stuff?

Paul
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
47,355
OH, and did you already install longer parking brake cables?
With 3.5" of lift the parking brake is the limiting factor in many cases. Then the brake hose. Then the shocks and maybe even the driveshaft.

The modern 9, 10 and 11 leaf packs actually flex pretty decent, but if you are running out of spring travel at this point before other limiting factors, then yes, longer, flatter and wider springs can net you a little more. As long as you don't run out of shackle movement.

For moving the rear hanger back, you do run out of space towards the rear pretty quickly, but you could integrated it into a heavy duty bumper mounting brace probably.
There's plenty of room to extend the front hanger, but you don't necessarily want things too off-center to the point of having to re-drill the center pin hole too far off of the center of the leaf pack.
Some trucks do that from the factory, so there is something to it. Not sure what factors you have to take into account though, once you start doing that.

Paul
 
OP
OP
P

patford

New Member
Joined
Dec 12, 2010
Messages
28
Has longer e-brake and flex brake line remove shocks to make sure they are not limiting things WH 2.5 leafs 11 pack . Put in 5.5 front coils with raise bucket and long arms so front way out flexs the back .
 

nvrstuk

Contributor
Just a Bronco driver for over 50 yrs!
Joined
Jul 31, 2001
Messages
8,614
Isn't the 63" GM spring swap popular?

I think RuffStuff even makes mounts and poly bushing brackets for them...super popular.

Disclaimer: I haven't done it, just know it's popular.

I would think with this long of a spring on an early Bronco it would really smooth out the ride and flex well...I have know idea what the spring rates are and whether you'd have to change those rates.
 

Broncobowsher

Total hack
Joined
Jun 4, 2002
Messages
34,835
Modern soft springs work really well. But as others have mentioned there are other limiting factors. I had to limit my rear travel with a set of sagged out 11 leaf nationals so the CV on the rear shaft didn't bind. That was with stock shock mounts and slightly longer shocks. I could stuff one tire to the bumpstop while the other limited by shock travel. Nothing fancy.
 

welndmn

Bronco Guru
Joined
Nov 12, 2001
Messages
2,112
Flex out your truck and see what's stopping it.
These bronco's are 40 years old now, while we all know what works, it's hard to know what you have now, or what has been hacked in by a previous owner,
I agree with Paul
E brake cables
Shocks
brake lines
Old stiff springs
over tightened shackle bolts
 
Top